Safety device for power-operated machines



H. E. SEAVER AND C. L. BOWERS. SAFETY DEVICE FOR POWER OPERATED MACHINES.

APPLICATION FILED JULY 10.1918.

' 1 54,345. Patented Sept. 28, 1920.

2 SHEETSSHEET INVENTOR.

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H. E. SEAVER AND C. L. BOWERS.

SAFETY DEVICE FOR POWER OPERATED MACHINES. APPLlCATlON FILED JULY 10.1918.

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UNITED STATES PATENT OFFICE.

HENRY E. SEAVER AND CI-IABLES L. BOVJER-S, OF HARTFORD, CONNECTICUT ASSIGNORS TO DANIEL M. WRIGI-IT, OF HARTFORD, CONNECTICUT.

SAFETY DEVICE FOR PONER-OPERATED MACHINES.

Specification of Letters Patent.

Patented Sept. 28, 1920.

Application filed July 10, 1918. Serial No. 244,139.

ToaZZ whom it may concern v Be it known that we, HENRY E. SEAVER and CHARLES L. Bownns, each a citizen of the UnitedStates, and a resident of Hartford, in the county of Hartford and State of Connecticut, have invented a new and Improved Safety Device for Power-Open ated Machines, of which the following is a specification.

This invention relates more especially to that class of safety devices employed to prevent a person from placing his hands or limbs in position to receive injury from moving parts of machinery, and an object of the invention, amongotners, is to provide a device of this class that shall be extremel eflective in operation and simple in construction. I

' One form of device embodying the invention and in the construction and use of which the objects hereinset out, as wellas others, may be attained, is illustrated in the accompanying drawings, in which- Figure 1 is a view in central vertical section through a machine showing this improved safety device applied thereto.

Fig. 2 is a view in side elevation 01; this .machine showing the improved safety device, the point of view being located in a direction at right angles to the point of view in Fig. 1.

Fig. 3 is a top plan view of the improved machine.

said machine comprising a base 10, having a rib 11, to receive the flanged lower edges or" oppositely arranged side parts 12 with guide supporting ribs 13 provided with guides 14 secured to the ribs in any suitable manner. Table supports 15 rest upon the side parts 12 and support a table 16, the side parts and table supports being secured together in any suitable manner. Boxes 17 underneath the table recelve a driving shaft 18 loosely supporting a driving pulley 19 at its outer end. A crank 20 is connected by a rod21 with a reciprocating support 22, said rod being journaled on a pin 23 extend ing across an opening in said support. Said support en ages the guides 14 in any suitable manner and springs 24 underneath the support steady its movement. Supporting columns 25 rise from opposite corners of the support 22, said support and the machine in general being of substantially rectangular form. A die head 26 is secured to the upper end of the columns and supports a die 27 positioned to cooperate with a lower die 28 secured to the table 16, said table having bushings 64through which the columns 25 extend. The upper die 27 is secured to a die holder 29 by means or" a shank 30 extending into said holder and held therein by a retaining screw 31. Positioning pins 32 are employed to position the die head.

A cage 35, preferably entirely surrounding the head and dies when it is in its lowermost position, said cage being of a height to absolutely prevent unintentional access to the space between the dies when in said lowermost position, is mounted to slide upon rods 36 to permit free access to the dies when in inoperative position. An actuating pin 37 projects from the lower part of the cage frame and is adapted to enter a plunger socket 38 secured to the side of the machine. A plunger 39 in this socket is seated upon a spring 40, a plunger rod 41 extending from the plunger being connected to a safety lever 57 pivotally secured to the side of the machine and having a safety arm 58 with a notch to engage a safety lug 59 on the side of a cam lever 48 to hold the latter in its operative position. A hand lever 42, pivotally attached to the side of the machine, has a bend intermediate its ends providing an oiiset end on said lever. A striking plate 43 is secured to the bent part of the lever in position to engage a latch 44 of a clutch mechanism that may be of any ordinary form and construction peculiarly applicable to machines of this class, the engagement of the lever with the latch positioning the latter out of the path of movement of a clutch pin 46 to be hereinafter described in order to avoid a clicking noise that would otherwise result by said pin striking said latch. Briefly described, the clutch mechanism embodies a clutch pin 45 in a socket in the pulley 19 to be engaged by a cotiperative spring pressed clutch pin 46 carried in a hub 47 secured tothe shaft 18. The pin 46 is held in its retracted position by the cam lever 48 lever. topermit it to readily enter said notch, the

' 20f the drawings.

that engages a notch in the under side of said pin. The latch 44 has a shoulder engaging the upper side of a latch plate 49 secured to the lever 48. Said lever is pressed upwardly by a spring (see Fig. 2) and the latch 44 is pivotally attached to an actuating lever 50 connected by a rod 51 with an arm 52 secured to a rock shaft 53 actuated by a treadle 54.

' hen the treadle is pushed downwardly the rod 51 will be pulled to swing the lever 50 on its pivot and pull the latch 44 downwardly'carrying with it the lever 48 and disengaging the latter from the notch in the side of the pin 46. Said pin is quickly moved by its spring into the path of the pin cam on said lever extending backwardly from said point, and by means of the cam the pin 46 is forced from engagement with the pin 45 when the shaft ,18 has made one complete rotation, with a result that the machine is automatically stopped at each com-' plete rotation of the. shaft 18.

The lever 42 maybe held in a lowered position by means of a catch plunger 55 having its end positioned to engage holes in the flange of a catch plate 56, as shown in Fig. The hand lever 42 has a slot 66 to'receive a pin 65 projecting from the side of the cam lever 48, and when the lever 42 is moved downwardly the engagement of the pin within said slot will-cause the lever 48 to be moved from disengagement with the clutchpin 46, and the machine will be thereby started in the manner just described, and when said hand lever is secured in its lower position, as above described, the machine will be continuously operated, for the reason that the lever 48 cannot move upwardly to engage the clutch pin 46 and disconnect it from its cociperating' pin. When the lever 42'is in its lowermost position the plate 43 thereon engages the edge of the latch 44' and holds it out ofthe path of movement ofthe clutch pin 46 and a clicking noise, by reason of engagement of said pin with said lever, is avoided, as hereinbefore described.

The cage 35 is held in its uppermost position by means of a counterweight 60. When the cage is in this position, the plunger 39 will be in its uppermost position and the safety lever 57 will be located to prevent movement of the lever 48, and consequently the machine cannot be started. Then, however, the cage 85 is pushed downwardly, as by hand, the pin 37 strikes the plunger 39 and through the connections above described,

the safety lever 57 is swung to disengage its 1 it will thus be seen that the machine cannot be started until the cage has been lowcred, and thecage cannot be placed in said lowered position so long asthe operatives fingers or hands are in the danger zones of the dies. Likewise in the normal operation of the machine by the treadle 54,"the parts are so fixed that the safety devices will be automatically set whenever the cage is raised and the operation of the machine is therebystopped, which operation, as above stated, cannot again take place until the cage'is lowered.

A closing plate 61 is secured to the side parts and a door plate 62 is attached to the front faces of said side parts to close an opening into a chamber between said side parts. i

I WVe elaim 1. lncombination with a member to start and stop a machine, a vertically 'movable cage completely surrounding active members of said machine and of aheight, when it is in its lowermost position, to effectually prevent inadvertent access to the danger zones of said active members, and aconnection between said cage and said starting and stopping memberfand including a lock to positively prevent operation of said member to start the machine when the cage is in a raised position.

2. The combination in a machine including stopping and starting mechanism in cluding means for automatically stoppingthe machine at each cycle of movement; of a cage movably'mountedto inclose operative parts of the machine, and a connection between said cage and said stopping and startmg mechanism to positively lock'the latter and prevent its'operation to start the machine before the cage is in its closed position, and to automatically stop the machine when the cage is moved to its open position.

3. In combination with a member to stop and start a machine including means to operate it to stop the machine at each cycle of movement thereof, and arranged to automatically'stop the machine, a cage movably mounted to prevent access to operative parts of the machine, and a connection between said cage and said stopping and starting member to positively lock the latter and prevent its operation to start the machine when the cage is in position to permit ac cess to said operative parts, said connection also setting the parts to cause operation of said stopping and starting member to stop the machine when the cage is in position to permit access to said operative parts.

a. In combination with a member to stop and start a machine embodying a reciproeating plunger, a cage surrounding said plunger and movable to prevent access thereto when the plunger is in operation, and a connection between said cage and said stopping and starting member to positively lock the latter to prevent its operation before the cage is in its closed position and also to set the parts to stop the machine when the cage is moved to its open position.

5. In combination with the stopping and starting mechanism of a machine and including a member to automatically stop the machine after it has completed a cycle of operation, a member to positively lock said mechanism and prevent its operation, a cage movably mounted to prevent access to operative parts of the machine, and an operative connection between said cage and said locking member.

6. A machine comprising a clutch mechanism including a pin clutch operating lever, means to positively lock said lever against movement, a plunger connected to said look ing means to operate it, and a movably mounted cage inclosing operative parts of said machine and'adapted to operate said plunger at the latter part of its movement to inclose said operative parts.

7. A machine comprising a clutch mechanism including a pin clutch operating lever, a locking lever to positively lock said operating lever against movement, a plunger connected to said locking lever to operate it, means for forcing said plunger to normally engage the locking lever with said operating lever, a cage movably mounted to inclose operative parts of said machine, and a pin projecting from said cage and adapted to strike said plunger.

HENRY E. SEAVER. CHARLES L. BOWERS. 

